1. Field of the Invention
The present invention relates to an organic light-emitting device and a light source device using an organic light-emitting device.
2. Background Art
As a related art, Patent document 1 (JP-A-2004-146121) discloses the following technique. That is, the technique aims to provide an organic electroluminescent device in which the leakage of light guided in a transparent substrate from a side surface of a transparent substrate and the extinction of the light inside the device can be prevented, and the light extraction efficiency is high. The technique relates to an organic electroluminescent device which is formed by providing an organic light-emitting layer between two electrodes and has a light-emitting section that allows the organic light-emitting layer to emit light by applying a voltage between the two electrodes. The organic electroluminescent device is configured such that a transparent electrode among the two electrodes is formed on a surface of a transparent substrate, a light reflection section is provided in an inner portion or an end portion of the transparent substrate at a position surrounding the light-emitting section, and even if light emitted from the light-emitting section is totally reflected at the interface between the surface of the transparent substrate and air and is guided in the transparent substrate, the guided light can be extracted from the surface of the transparent substrate by reflecting the guided light by the light reflection section.
Further, Patent document 2 (JP-A-8-138870) discloses the following technique. That is, the technique aims to provide an organic thin-film EL device in which a specular electrode of an organic thin-film EL element is hardly visually recognized as a specular surface also when the element does not emit light. The organic thin-film EL device is configured such that the device includes: an organic thin-film EL element having a laminate obtained by laminating a transparent substrate, a transparent electrode formed on one principal surface of the transparent substrate, and a specular electrode formed on the transparent electrode with at least an organic light-emitting layer interposed therebetween; and a reflection section which covers the organic thin-film EL element and the transparent substrate except for a portion of a side surface of the transparent substrate, and light emitted from the organic thin-film EL element is emitted to the outside from the portion which is not covered with the reflection section among the side surfaces of the transparent substrate.
However, in the configuration described in Patent document 1, the reflector is formed only in a side surface and an inner portion of the substrate, and therefore, part of light reflected by the reflector exits ahead of the substrate to contribute to the improvement of the light extraction efficiency, however, on the other hand, part of light propagates behind the substrate to directly become a loss, and therefore, it is difficult to efficiently extract light trapped in the substrate. Further, in the configuration described in Patent document 2, light is extracted only from the side surface, and therefore, the multiple reflection loss of light accompanying the propagation of light in the device is large, and it is difficult to extract a sufficient amount of light to the outside.